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Omar OMF, Kimble AL, Cheemala A, Tyburski JD, Pandey S, Wu Q, Reese B, Jellison ER, Li Y, Hao B, Yan R, Murphy PA. Targeted inCITE-Seq Analysis Identifies the Loss of Nuclear TDP-43 in Endothelium as a Mediator of Blood Brain Barrier Signaling Pathway Dysfunction in Neurodegeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.13.571178. [PMID: 38168276 PMCID: PMC10760156 DOI: 10.1101/2023.12.13.571178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Despite the importance of the endothelium in the regulation of the blood brain barrier (BBB) in aging and neurodegenerative disease, difficulties in extracting endothelial cell (EC) nuclei have limited analysis of these cells. In addition, nearly all Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Degeneration (FTD), and a large portion of Alzheimer's Disease (AD) exhibit neuronal TDP-43 aggregation, leading to loss of nuclear function, but whether TDP-43 is similarly altered in human BBB ECs is unknown. Here we utilize a novel technique for the enrichment of endothelial and microglial nuclei from human cortical brain tissues, combined with inCITE-seq, to analyze nuclear proteins and RNA transcripts in a large cohort of healthy and diseased donors. Our findings reveal a unique transcriptional signature in nearly half of the capillary endothelial cells across neurodegenerative states, characterized by reduced levels of nuclear β-Catenin and canonical downstream genes, and an increase in TNF/NF-kB target genes. We demonstrate that this does not correlate with increased nuclear p65/NF-kB, but rather a specific loss of nuclear TDP-43 in these disease associated ECs. Comparative analysis in animal models with targeted disruption of TDP-43 shows that this is sufficient to drive these transcriptional alterations. This work reveals that TDP-43 is a critical governor of the transcriptional output from nuclear p65/NF-kB, which has paradoxical roles in barrier maintenance and also barrier compromising inflammatory responses, and suggests that disease specific loss in ECs contributes to BBB defects observed in the progression of AD, ALS and FTD.
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Affiliation(s)
- Omar M F Omar
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
| | - Amy L Kimble
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
| | - Ashok Cheemala
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
| | - Jordan D Tyburski
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
| | - Swati Pandey
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
| | - Qian Wu
- Department of Pathology, University of Connecticut Medical School, Farmington CT
| | - Bo Reese
- Center for Genome Innovation, University of Connecticut, Storrs CT
| | - Evan R Jellison
- Department of Immunology, University of Connecticut Medical School, Farmington CT
| | - Yunfeng Li
- Department of Molecular Biology and Biophysics, Farmington CT
| | - Bing Hao
- Department of Molecular Biology and Biophysics, Farmington CT
| | - Riqiang Yan
- Department of Neuroscience, University of Connecticut Medical School, Farmington CT
| | - Patrick A Murphy
- Center for Vascular Biology, University of Connecticut Medical School, Farmington CT
- Department of Immunology, University of Connecticut Medical School, Farmington CT
- Department of Neuroscience, University of Connecticut Medical School, Farmington CT
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2
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Ta HQ, Teman NR, Kron IL, Roeser ME, Laubach VE. Steen solution protects pulmonary microvascular endothelial cells and preserves endothelial barrier after lipopolysaccharide-induced injury. J Thorac Cardiovasc Surg 2023; 165:e5-e20. [PMID: 35577593 PMCID: PMC9576825 DOI: 10.1016/j.jtcvs.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Acute respiratory distress syndrome represents the devastating result of acute lung injury, with high mortality. Limited methods are available for rehabilitation of lungs affected by acute respiratory distress syndrome. Our laboratory has demonstrated rehabilitation of sepsis-injured lungs via normothermic ex vivo and in vivo perfusion with Steen solution (Steen). However, mechanisms responsible for the protective effects of Steen remain unclear. This study tests the hypothesis that Steen directly attenuates pulmonary endothelial barrier dysfunction and inflammation induced by lipopolysaccharide. METHODS Primary pulmonary microvascular endothelial cells were exposed to lipopolysaccharide for 4 hours and then recovered for 8 hours in complete media (Media), Steen, or Steen followed by complete media (Steen/Media). Oxidative stress, chemokines, permeability, interendothelial junction proteins, and toll-like receptor 4-mediated pathways were assessed in pulmonary microvascular endothelial cells using standard methods. RESULTS Lipopolysaccharide treatment of pulmonary microvascular endothelial cells and recovery in Media significantly induced reactive oxygen species, lipid peroxidation, expression of chemokines (eg, chemokine [C-X-C motif] ligand 1 and C-C motif chemokine ligand 2) and cell adhesion molecules (P-selectin, E-selectin, and vascular cell adhesion molecule 1), permeability, neutrophil transmigration, p38 mitogen-activated protein kinase and nuclear factor kappa B signaling, and decreased expression of tight and adherens junction proteins (zonula occludens-1, zonula occludens-2, and vascular endothelial-cadherin). All of these inflammatory pathways were significantly attenuated after recovery of pulmonary microvascular endothelial cells in Steen or Steen/Media. CONCLUSIONS Steen solution preserves pulmonary endothelial barrier function after lipopolysaccharide exposure by promoting an anti-inflammatory environment via attenuation of oxidative stress, toll-like receptor 4-mediated signaling, and conservation of interendothelial junctions. These protective mechanisms offer insight into the advancement of methods for in vivo lung perfusion with Steen for the treatment of severe acute respiratory distress syndrome.
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Affiliation(s)
| | | | | | | | - Victor E. Laubach
- Address for reprints: Victor E. Laubach, PhD, Department of Surgery, University of Virginia School of Medicine, PO Box 801359, Charlottesville, VA 22908
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3
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Airway Epithelial Cell Junctions as Targets for Pathogens and Antimicrobial Therapy. Pharmaceutics 2022; 14:pharmaceutics14122619. [PMID: 36559113 PMCID: PMC9786141 DOI: 10.3390/pharmaceutics14122619] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
Intercellular contacts between epithelial cells are established and maintained by the apical junctional complexes (AJCs). AJCs conserve cell polarity and build epithelial barriers to pathogens, inhaled allergens, and environmental particles in the respiratory tract. AJCs consist of tight junctions (TJs) and adherens junctions (AJs), which play a key role in maintaining the integrity of the airway barrier. Emerging evidence has shown that different microorganisms cause airway barrier dysfunction by targeting TJ and AJ proteins. This review discusses the pathophysiologic mechanisms by which several microorganisms (bacteria and viruses) lead to the disruption of AJCs in airway epithelial cells. We present recent progress in understanding signaling pathways involved in the formation and regulation of cell junctions. We also summarize the potential chemical inhibitors and pharmacological approaches to restore the integrity of the airway epithelial barrier. Understanding the AJCs-pathogen interactions and mechanisms by which microorganisms target the AJC and impair barrier function may further help design therapeutic innovations to treat these infections.
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4
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Brown MA, Jabeen M, Bharj G, Hinks TSC. Non-typeable Haemophilus influenzae airways infection: the next treatable trait in asthma? Eur Respir Rev 2022; 31:220008. [PMID: 36130784 PMCID: PMC9724834 DOI: 10.1183/16000617.0008-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 07/04/2022] [Indexed: 11/05/2022] Open
Abstract
Asthma is a complex, heterogeneous condition that affects over 350 million people globally. It is characterised by bronchial hyperreactivity and airways inflammation. A subset display marked airway neutrophilia, associated with worse lung function, higher morbidity and poor response to treatment. In these individuals, recent metagenomic studies have identified persistent bacterial infection, particularly with non-encapsulated strains of the Gram-negative bacterium Haemophilus influenzae. Here we review knowledge of non-typeable H. influenzae (NTHi) in the microbiology of asthma, the immune consequences of mucosal NTHi infection, various immune evasion mechanisms, and the clinical implications of NTHi infection for phenotyping and targeted therapies in neutrophilic asthma. Airway neutrophilia is associated with production of neutrophil chemokines and proinflammatory cytokines in the airways, including interleukin (IL)-1β, IL-6, IL-8, IL-12, IL-17A and tumour necrosis factor. NTHi adheres to and invades the lower respiratory tract epithelium, inducing the NLR family pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasomes. NTHi reduces expression of tight-junction proteins, impairing epithelial integrity, and can persist intracellularly. NTHi interacts with rhinoviruses synergistically via upregulation of intracellular cell adhesion molecule 1 and promotion of a neutrophilic environment, to which NTHi is adapted. We highlight the clinical relevance of this emerging pathogen and its relevance for the efficacy of long-term macrolide therapy in airways diseases, we identify important unanswered questions and we propose future directions for research.
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Affiliation(s)
- Mary Ashley Brown
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
| | - Maisha Jabeen
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
| | - Gurpreet Bharj
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
- Mammalian Genetics Unit, MRC Harwell Institute, Oxford, UK
| | - Timothy S C Hinks
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
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5
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Yuan S, Li Y, Li J, Xue JC, Wang Q, Hou XT, Meng H, Nan JX, Zhang QG. Traditional Chinese Medicine and Natural Products: Potential Approaches for Inflammatory Bowel Disease. Front Pharmacol 2022; 13:892790. [PMID: 35873579 PMCID: PMC9301246 DOI: 10.3389/fphar.2022.892790] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/16/2022] [Indexed: 11/25/2022] Open
Abstract
Inflammatory bowel disease (IBD) is a rare, recurrent, and intractable inflammation obstruction of the stomach tract, usually accompanied by inflammation of cell proliferation and inflammation of the colon and carries a particular cause of inflammation. The clinical use of drugs in western countries affects IBD treatment, but various adverse effects and high prices limit their application. For these reasons, Traditional Chinese Medicine (TCM) is more advantageous in treating IBD. This paper reviews the mechanism and research status of TCM and natural products in IBD treatment by analyzing the relevant literature to provide a scientific and theoretical basis for IBD treatment.
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Affiliation(s)
- Shuo Yuan
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China.,Chronic Disease Research Center, Medical College, Dalian University, Dalian, China
| | - You Li
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China
| | - Jiao Li
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China.,Department of Immunology and Pathogenic Biology, Yanbian University College of Basic Medicine, Yanji, China
| | - Jia-Chen Xue
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China.,Department of Immunology and Pathogenic Biology, Yanbian University College of Basic Medicine, Yanji, China
| | - Qi Wang
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China
| | - Xiao-Ting Hou
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China
| | - Huan Meng
- Chronic Disease Research Center, Medical College, Dalian University, Dalian, China
| | - Ji-Xing Nan
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Qing-Gao Zhang
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China.,Chronic Disease Research Center, Medical College, Dalian University, Dalian, China.,Department of Immunology and Pathogenic Biology, Yanbian University College of Basic Medicine, Yanji, China
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6
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Godbole NM, Chowdhury AA, Chataut N, Awasthi S. Tight Junctions, the Epithelial Barrier, and Toll-like Receptor-4 During Lung Injury. Inflammation 2022; 45:2142-2162. [PMID: 35779195 DOI: 10.1007/s10753-022-01708-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/31/2022] [Accepted: 06/13/2022] [Indexed: 11/25/2022]
Abstract
Lung epithelium is constantly exposed to the environment and is critically important for the orchestration of initial responses to infectious organisms, toxins, and allergic stimuli, and maintenance of normal gaseous exchange and pulmonary function. The integrity of lung epithelium, fluid balance, and transport of molecules is dictated by the tight junctions (TJs). The TJs are formed between adjacent cells. We have focused on the topic of the TJ structure and function in lung epithelial cells. This review includes a summary of the last twenty years of literature reports published on the disrupted TJs and epithelial barrier in various lung conditions and expression and regulation of specific TJ proteins against pathogenic stimuli. We discuss the molecular signaling and crosstalk among signaling pathways that control the TJ structure and function. The Toll-like receptor-4 (TLR4) recognizes the pathogen- and damage-associated molecular patterns released during lung injury and inflammation and coordinates cellular responses. The molecular aspects of TLR4 signaling in the context of TJs or the epithelial barrier are not fully known. We describe the current knowledge and possible networking of the TLR4-signaling with cellular and molecular mechanisms of TJs, lung epithelial barrier function, and resistance to treatment strategies.
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Affiliation(s)
- Nachiket M Godbole
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, 1110 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA
| | - Asif Alam Chowdhury
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, 1110 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA
| | - Neha Chataut
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, 1110 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA
| | - Shanjana Awasthi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Oklahoma Health Sciences Center, 1110 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA.
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7
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Wang Y, Wu Y, Liu B, Yang H, Qian H, Cheng Y, Li X, Yang G, Zheng X, Shen F. Binding domain peptide ameliorates alveolar hypercoagulation and fibrinolytic inhibition in mice with lipopolysaccharide-induced acute respiratory distress syndrome Via NF-κB signaling pathway. Am J Transl Res 2022; 14:3854-3863. [PMID: 35836863 PMCID: PMC9274609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/07/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Alveolar hypercoagulation and fibrinolytic inhibition are shown to be associated with refractory hypoxemia in acute respiratory distress syndrome (ARDS), and the NF-κB pathway is involved in this process. The purpose of this study is to explore the role of NEMO-binding domain peptide (NBDP) in alleviating alveolar hypercoagulation and fibrinolytic inhibition induced by lipopolysaccharide (LPS) in ARDS mice and its related mechanisms. MATERIALS AND METHODS ARDS was induced by inhalation of LPS (mg/L) in adult male BALB/c mice. Mice were treated with intratracheal inhalation of NBDP or saline aerosol at increased concentrations 30 minutes before LPS administration. Six hours after LPS treatment, bronchoalveolar lavage fluids (BALF) were collected and then all mice were euthanized. In addition, coagulation and fibrinolysis associated factors in lung tissues and BALF were detected, and the activation of NF-κB signaling pathway was observed. RESULTS NBDP pretreatment dose-dependently inhibited the expression of tissue factor (TF) and plasminogen activator inhibitor (PAI) 1 in lung tissues, reduced the secretions of TF, PAI-1, thrombin-antithrombin (TAT) complex, and promoted activated protein C (APC) secretion in BALF induced by LPS. LPS-induced high expression of pulmonary procollagen peptide type lll (PIIIP) was also reduced in a dose-dependent manner under NBDP pretreatment. Western blotting showed that NBDP pretreatment significantly attenuated LPS-induced activation of IKKα/β, Iκα and NF-κB p65. NBDP pretreatment also inhibited the DNA binding activity of p65 induced by LPS. We also noticed that NBDP protected mice against LPS-induced lung injury in a dose-dependent manner. CONCLUSIONS The experimental findings demonstrate that through inhibiting the NF-κB signaling pathway, NBDP dose-dependently ameliorates LPS-induced alveolar hypercoagulation and fibrinolytic inhibition, which is expected to be a new therapeutic target to correct the abnormalities of alveolar coagulation and fibrinolytic pathways in ARDS.
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Affiliation(s)
- Yahui Wang
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
- Department of Intensive Care Unit, The People’s Hospital of Weining CountyWeining County 553100, Guizhou, China
| | - Yanqi Wu
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Bo Liu
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Huilin Yang
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Hong Qian
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Yumei Cheng
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Xiang Li
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Guixia Yang
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Xinghao Zheng
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
| | - Feng Shen
- Department of Intensive Care Unit, Guizhou Medical University Affiliated HospitalGuiyang 550001, Guizhou, China
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8
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Shirvaliloo M. The blood-gas barrier in COVID-19: an overview of the effects of SARS-CoV-2 infection on the alveolar epithelial and endothelial cells of the lung. Tissue Barriers 2021; 9:1937013. [PMID: 34232823 PMCID: PMC8794501 DOI: 10.1080/21688370.2021.1937013] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/21/2021] [Accepted: 05/25/2021] [Indexed: 02/08/2023] Open
Abstract
Blood-gas barrier (BGB) or alveolar-capillary barrier is the primary tissue barrier affected by coronavirus disease 2019 (COVID-19). Comprising alveolar epithelial cells (AECs), endothelial cells (ECs) and the extracellular matrix (ECM) in between, the BGB is damaged following the action of multiple pro-inflammatory cytokines during acute inflammation. The infection of AECs and ECs with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen behind COVID-19, triggers an inflammatory response at the BGB, inducing the release of interleukin 1 (IL-1), IL-6, tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), high mobility group box 1 (HMGB1), matrix metalloproteinases (MMPs), intercellular adhesion molecule-1 (ICAM-1) and platelet activating factor (PAF). The end result is the disassembly of adherens junctions (AJs) and tight junctions (TJs) in both AECs and ECs, AEC hyperplasia, EC pyroptosis, ECM remodeling and deposition of fibrin clots in the alveolar capillaries, leading to disintegration and thickening of the BGB, and ultimately, hypoxia. This commentary seeks to provide a brief account of how the BGB might become affected in COVID-19.
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Affiliation(s)
- Milad Shirvaliloo
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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9
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Lynn KS, Easley KF, Martinez FJ, Reed RC, Schlingmann B, Koval M. Asymmetric distribution of dynamin-2 and β-catenin relative to tight junction spikes in alveolar epithelial cells. Tissue Barriers 2021; 9:1929786. [PMID: 34107845 DOI: 10.1080/21688370.2021.1929786] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Tight junctions between lung alveolar epithelial cells maintain an air-liquid barrier necessary for healthy lung function. Previously, we found that rearrangement of tight junctions from a linear, cortical orientation into perpendicular protrusions (tight junction spikes) is associated with a decrease in alveolar barrier function, especially in alcoholic lung syndrome. Using quantitative super-resolution microscopy, we found that spikes in control cells were enriched for claudin-18 as compared with alcohol-exposed cells. Moreover, using an in situ method to measure barrier function, tight junction spikes were not associated with localized increases in permeability. This suggests that tight junction spikes have a regulatory role as opposed to causing a physical weakening of the epithelial barrier. We found that tight junction spikes form at cell-cell junctions oriented away from pools of β-catenin associated with actin filaments, suggesting that adherens junctions determine the directionality of tight junction spikes. Dynamin-2 was associated with junctional claudin-18 and ZO-1, but showed little localization with β-catenin and tight junction spikes. Treatment with Dynasore decreased the number of tight junction spikes/cell, increased tight junction spike length, and stimulated actin to redistribute to cortical tight junctions. By contrast, Dynole 34-2 and MiTMAB altered β-catenin localization, and reduced tight junction spike length. These data suggest a novel role for dynamin-2 in tight junction spike formation by reorienting junction-associated actin. Moreover, the greater spatial separation of adherens and tight junctions in squamous alveolar epithelial cells as compared with columnar epithelial cells facilitates analysis of molecular regulation of the apical junctional complex.
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Affiliation(s)
- K Sabrina Lynn
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA
| | - Kristen F Easley
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA
| | - Francisco J Martinez
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA
| | - Ryan C Reed
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA
| | - Barbara Schlingmann
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, USA.,Department of Cell Biology, Emory University School of Medicine, Atlanta, USA
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10
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Bo L, Jin F, Ma Z, Li C. Redox signaling and antioxidant therapies in acute respiratory distress syndrome: a systematic review and meta-analysis. Expert Rev Respir Med 2021; 15:1355-1365. [PMID: 33928830 DOI: 10.1080/17476348.2021.1924681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Objectives: No pharmacologic treatment that targets the pathophysiologic alterations of acute respiratory distress syndrome (ARDS) has proven effective. Previous studies have revealed overactive oxidative stress as a potential therapeutic target. Thus we conducted this systematic review to assess the efficacyof antioxidant therapy on the clinical outcomes of ARDS patients.Methods: We retrieved clinical trials from electronic databases. Articles and conference abstracts about antioxidant therapies for patients with ARDS were identified in which the overall effect of each antioxidant therapy on the mortality of ARDS patients was summarized.Results: We identified 18 relevant studies that met the inclusion criteria, including 899 patients in the experimental group and 870 patients in the control group. The pooled results indicated that most antioxidant therapies could not improve all-cause mortality and might even be harmful in ARDS patients at low risk of death.Conclusion: Unclassified patients could not benefit from the antioxidant therapies, and thus discretion must be exercised when using these therapies.Abbreviations ARDS: Acute respiratory distress syndrome; ICU: Intensive care unit; NAC: N-acetylcysteine; ROS: Reactive oxygen species; RNS: Reactive nitrogen species; RR: Relative risk; CI: Confidence interval; OTC: L-2-oxothiazolidine-4-carboxylic acid; EPA: Eicosapentaenoic acid; DHA: Docosahexaenoic acid; GLA: Gamma-linolenic acid; NA: Not applicable; PaO2/FiO2 ratio: The ratio of partial pressure arterial oxygen and fraction of inspired oxygen; ALI: Acute lung injury.
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Affiliation(s)
- Liyan Bo
- Department of Respiratory and Critical Care Medicine, General Hospital of Northern Theater Command, Shenyang, China.,Department of Respiratory and Critical Care Medicine, Chest Hospital of Xi'an, Xi'an, China
| | - Faguang Jin
- Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital, Air Force Medical University, Xi'an, China
| | - Zhuang Ma
- Department of Respiratory and Critical Care Medicine, General Hospital of Northern Theater Command, Shenyang, China
| | - Congcong Li
- Department of Respiratory and Critical Care Medicine, General Hospital of Northern Theater Command, Shenyang, China
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11
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Weight CM, Jochems SP, Adler H, Ferreira DM, Brown JS, Heyderman RS. Insights Into the Effects of Mucosal Epithelial and Innate Immune Dysfunction in Older People on Host Interactions With Streptococcus pneumoniae. Front Cell Infect Microbiol 2021; 11:651474. [PMID: 34113578 PMCID: PMC8185287 DOI: 10.3389/fcimb.2021.651474] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 05/10/2021] [Indexed: 12/21/2022] Open
Abstract
In humans, nasopharyngeal carriage of Streptococcus pneumoniae is common and although primarily asymptomatic, is a pre-requisite for pneumonia and invasive pneumococcal disease (IPD). Together, these kill over 500,000 people over the age of 70 years worldwide every year. Pneumococcal conjugate vaccines have been largely successful in reducing IPD in young children and have had considerable indirect impact in protection of older people in industrialized country settings (herd immunity). However, serotype replacement continues to threaten vulnerable populations, particularly older people in whom direct vaccine efficacy is reduced. The early control of pneumococcal colonization at the mucosal surface is mediated through a complex array of epithelial and innate immune cell interactions. Older people often display a state of chronic inflammation, which is associated with an increased mortality risk and has been termed 'Inflammageing'. In this review, we discuss the contribution of an altered microbiome, the impact of inflammageing on human epithelial and innate immunity to S. pneumoniae, and how the resulting dysregulation may affect the outcome of pneumococcal infection in older individuals. We describe the impact of the pneumococcal vaccine and highlight potential research approaches which may improve our understanding of respiratory mucosal immunity during pneumococcal colonization in older individuals.
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Affiliation(s)
- Caroline M. Weight
- Research Department of Infection, Division of Infection and Immunity, University College London, London, United Kingdom
| | - Simon P. Jochems
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Hugh Adler
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- Tropical and Infectious Diseases Unit, Liverpool University Hospitals National Health Service (NHS) Foundation Trust, Liverpool, United Kingdom
| | - Daniela M. Ferreira
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Jeremy S. Brown
- Respiratory Medicine, University College London, London, United Kingdom
| | - Robert S. Heyderman
- Research Department of Infection, Division of Infection and Immunity, University College London, London, United Kingdom
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12
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Geng P, Yu F, Tan D, Xu J, Yang Y, Xu M, Wang H, Ling B. Involvement of claudin-5 in H 2S-induced acute lung injury. J Toxicol Sci 2020; 45:293-304. [PMID: 32404561 DOI: 10.2131/jts.45.293] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Acute exposure to hydrogen sulfide (H2S) can cause fatal acute lung injury (ALI). However, the mechanisms of H2S-induced ALI are still not fully understood. This study aims to investigate the role of the tight junction protein claudin-5 in H2S-induced ALI. In our study, Sprague-Dawley (SD) rats were exposed to H2S to establish the ALI model, and in parallel, human pulmonary microvascular endothelial cells (HPMECs) were incubated with NaHS (a H2S donor) to establish a cell model. Lung immunohistochemistry and electron microscopy assays were used to identify H2S-induced ALI, and the expression of claudin-5, p-AKT/t-AKT and p-FoxO1/t-FoxO1 was detected. Our results show that H2S promoted the formation of ALI by morphological investigation and decreased claudin-5 expression. Dexamethasone (Dex) could partly attenuate NaHS-mediated claudin-5 downregulation, and the protective effects of Dex could be partially blocked by LY294002, a PI3K/AKT/FoxO1 pathway antagonist. Moreover, as a consequence of the altered phosphorylation of AKT and FoxO1, a change in claudin-5 with the same trend was observed. Therefore, the tight junction protein claudin-5 might be considered a therapeutic target for the treatment of ALI induced by H2S and other hazardous gases.
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Affiliation(s)
- Ping Geng
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Fen Yu
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Dingyu Tan
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Jiyang Xu
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Yan Yang
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Min Xu
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Huihui Wang
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
| | - Bingyu Ling
- Department of Emergency Medicine, Northern Jiangsu People's Hospital, Yangzhou University College of Clinical Medicine, China
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13
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Stolte KN, Pelz C, Yapto CV, Raguse JD, Dommisch H, Danker K. IL-1β strengthens the physical barrier in gingival epithelial cells. Tissue Barriers 2020; 8:1804249. [PMID: 32835592 DOI: 10.1080/21688370.2020.1804249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Periodontitis is one of the most common oral diseases worldwide and is caused by a variety of interactions between oral bacteria and the host. Here, pathogens induce inflammatory host responses that cause the secretion of proinflammatory cytokines such as IL-1β, IL-6, and IL-8 by oral epithelial cells. In various systems, it has been shown that inflammation compromises physical barriers, which enables bacteria to invade the tissue. In this study, we investigated the barrier properties of the oral mucosa under physiological and inflamed conditions. For this purpose, we assessed the influence of IL-1β on the transepithelial electrical resistance and in particular on tight junctions in vitro in human stratified squamous epithelium models. Indirect immunofluorescence and western blot analyses were performed to investigate localization and expression of tight junction proteins in primary gingival cells, immortalized gingival cells and native gingiva. Furthermore, the TEER of gingival keratinocytes was assessed. The results showed that IL-1β led to strengthening of the gingival keratinocyte barrier. This was demonstrated by an increase in TEER, the upregulation of TJ proteins, and an increase in the formation of TJ strands. The IL-1β-mediated upregulation of occludin was prevented by the NF-κB inhibitor BAY 11-7085. These observations provide insights into host responses in the early stages of periodontal disease and offer information about TJ formation in human gingival epithelial cells under physiological and inflammatory conditions. Comprehensive knowledge of the physical barrier during inflammation may help in developing strategies to effectively target the inflammatory barrier to improve the bioavailability of drugs for the treatment of periodontitis.
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Affiliation(s)
- Kim Natalie Stolte
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Institute for Biochemistry , Berlin, Germany
| | - Carsten Pelz
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Institute for Biochemistry , Berlin, Germany
| | - Cynthia V Yapto
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Institute for Biochemistry , Berlin, Germany
| | - Jan-Dirk Raguse
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Department of Oral and Maxillofacial Surgery, Berlin, Germany
| | - Henrik Dommisch
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Department of Periodontology and Synoptic Dentistry, Berlin, Germany.,Department of Periodontics, University of Washington , Seattle, WA, USA
| | - Kerstin Danker
- Charitá - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Berlin Institute of Health.,Institute for Biochemistry , Berlin, Germany
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14
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Lynn KS, Peterson RJ, Koval M. Ruffles and spikes: Control of tight junction morphology and permeability by claudins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183339. [PMID: 32389670 DOI: 10.1016/j.bbamem.2020.183339] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 04/24/2020] [Accepted: 05/01/2020] [Indexed: 02/06/2023]
Abstract
Epithelial barrier function is regulated by a family of transmembrane proteins known as claudins. Functional tight junctions are formed when claudins interact with other transmembrane proteins, cytosolic scaffold proteins and the actin cytoskeleton. The predominant scaffold protein, zonula occludens-1 (ZO-1), directly binds to most claudin C-terminal domains, crosslinking them to the actin cytoskeleton. When imaged by immunofluorescence microscopy, tight junctions most frequently are linear structures that form between tricellular junctions. However, tight junctions also adapt non-linear architectures exhibiting either a ruffled or spiked morphology, which both are responses to changes in claudin engagement of actin filaments. Other terms for ruffled tight junctions include wavy, tortuous, undulating, serpentine or zig-zag junctions. Ruffling is under the control of hypoxia induced factor (HIF) and integrin-mediated signaling, as well as direct mechanical stimulation. Tight junction ruffling is specifically enhanced by claudin-2, antagonized by claudin-1 and requires claudin binding to ZO-1. Tight junction spikes are sites of active vesicle budding and fusion that appear as perpendicular projections oriented towards the nucleus. Spikes share molecular features with focal adherens junctions and tubulobulbar complexes found in Sertoli cells. Lung epithelial cells under stress form spikes due to an increase in claudin-5 expression that directly disrupts claudin-18/ZO-1 interactions. Together this suggests that claudins are not simply passive cargoes controlled by scaffold proteins. We propose a model where claudins specifically influence tight junction scaffold proteins to control interactions with the cytoskeleton as a mechanism that regulates tight junction assembly and function.
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Affiliation(s)
- K Sabrina Lynn
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Raven J Peterson
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Koval
- Division of Pulmonary, Allergy Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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15
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Umstead TM, Hewage EK, Mathewson M, Beaudoin S, Chroneos ZC, Wang M, Halstead ES. Lower respiratory tract delivery, airway clearance, and preclinical efficacy of inhaled GM-CSF in a postinfluenza pneumococcal pneumonia model. Am J Physiol Lung Cell Mol Physiol 2020; 318:L571-L579. [PMID: 31994895 DOI: 10.1152/ajplung.00296.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Inhaled granulocyte/macrophage colony-stimulating factor (GM-CSF) shows promise as a therapeutic to treat viral and bacterial pneumonia, but no mouse model of inhaled GM-CSF has been described. We sought to 1) develop a mouse model of aerosolized recombinant mouse GM-CSF administration and 2) investigate the protection conferred by inhaled GM-CSF during influenza A virus (IAV) infection against secondary bacterial infection with pneumococcus. To assess lower respiratory tract delivery of aerosolized therapeutics, mice were exposed to aerosolized fluorescein (FITC)-labeled dextran noninvasively via an aerosolization tower or invasively using a rodent ventilator. The efficiency of delivery to the lower respiratory tracts of mice was 0.01% noninvasively compared with 0.3% invasively. The airway pharmacokinetics of inhaled GM-CSF fit a two-compartment model with a terminal phase half-life of 1.3 h. To test if lower respiratory tract levels were sufficient for biological effect, mice were infected intranasally with IAV, treated with aerosolized recombinant mouse GM-CSF, and then secondarily infected with Streptococcus pneumoniae. Inhaled GM-CSF conferred a significant survival benefit to mice against secondary challenge with S. pneumoniae (P < 0.05). Inhaled GM-CSF did not reduce airway or lung parenchymal bacterial growth but significantly reduced the incidence of S. pneumoniae bacteremia (P < 0.01). However, GM-CSF overexpression during influenza virus infection did not affect lung epithelial permeability to FITC-dextran ingress into the bloodstream. Therefore, the mechanism of protection conferred by inhaled GM-CSF appears to be locally mediated improved lung antibacterial resistance to systemic bacteremia during IAV infection.
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Affiliation(s)
- Todd M Umstead
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Eranda Kurundu Hewage
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Margaret Mathewson
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Sarah Beaudoin
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Zissis C Chroneos
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Department of Microbiology and Immunology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Ming Wang
- Department of Public Health Sciences, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - E Scott Halstead
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania.,Pulmonary Immunology and Physiology Laboratory, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
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16
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M T, T A, B S, Ak G, Sks S. Curcumin prophylaxis refurbishes alveolar epithelial barrier integrity and alveolar fluid clearance under hypoxia. Respir Physiol Neurobiol 2019; 274:103336. [PMID: 31778793 DOI: 10.1016/j.resp.2019.103336] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/30/2019] [Accepted: 11/07/2019] [Indexed: 12/19/2022]
Abstract
We have studied the prophylactic efficacy of curcumin to ameliorate the impairment of tight junction protein integrity and fluid clearance in lungs of rats under hypoxia. A549 cells wereexposed to 3 % O2 for 1 h, 3 h, 6 h, 12 h, 24 h and 48 h and rats were exposed to 7620 m for 6 h. NF-κB, Hif-1α and their related genes, tight junction protein (TJ) (ZO-1, JAM-C, claudin-4 and claudin-5, claudin-18) expressions were determined in A549 cells and lungs of rats by western blotting, ELISA and their activity by reporter gene assay, siRNAp65 knock out. Tissue specific localization of tight junction protein was determined by immunohistochemistry and immunoflorescence. Further transmission electron microscopy (TEM) was used to visualize the TJ structures between pulmonary epithelial cells. Blood gas and hematological parameters were also assessed. Later we checked, whether prior treatment with curcumin can restore the altered alveolar epithelial barrier integrity that is compromised through inflammatory mediators under hypoxia, A549 cells were pre-treated (1 h) with 10 μM curcumin and rats with 50 mg curcumin/kg BW and exposed to hypoxia. Curcumin pre-treatment both in vitro and in vivo showed significant changes in TJ protein integrity, attenuated NF-κB activity with reduced expression of its regulatory genes in lung tissues, serum and bronchoalveolar lavage fluid (BALF) along with stabilized HIF-1α levels under hypoxia. NF-κB inhibitors MG132, SN50 or siRNA mediated p65 knock down significantly reduced the dextran FITC influx into the lungs. The present study indicates that, curcumin prophylaxis augments alveolar epithelial barrier integrity and alveolar fluid clearance under hypoxia.
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Affiliation(s)
- Titto M
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Ankit T
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Saumya B
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Gausal Ak
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Sarada Sks
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
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17
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Stueckle TA, White A, Wagner A, Gupta RK, Rojanasakul Y, Dinu CZ. Impacts of Organomodified Nanoclays and Their Incinerated Byproducts on Bronchial Cell Monolayer Integrity. Chem Res Toxicol 2019; 32:2445-2458. [PMID: 31698904 DOI: 10.1021/acs.chemrestox.9b00277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Incorporation of engineered nanomaterials (ENMs) into nanocomposites using advanced manufacturing strategies is set to revolutionize diverse technologies. Of these, organomodified nanoclays (ONCs; i.e., smectite clays with different organic coatings) act as nanofillers in applications ranging from automotive to aerospace and biomedical systems. Recent toxicological evaluations increased awareness that exposure to ONC can occur along their entire life cycle, namely, during synthesis, handling, use, manipulation, and disposal. Compared to other ENMs, however, little information exists describing which physicochemical properties contribute to induced health risk. This study conducted high content screening on bronchial epithelial cell monolayers for coupled high-throughput in vitro assessment strategies aimed to evaluate acute toxicity of a library of ONCs (all of prevalent use) prior to and after simulated disposal by incineration. Coating-, incineration status-, and time-dependent effects were considered to determine changes in the pulmonary monolayer integrity, cell transepithelial resistance, apoptosis, and cell metabolism. Results showed that after exposure to each ONC at its half-maximal inhibitory concentration (IC50) there is a material-induced toxicity effect with pristine nanoclay, for instance, displaying acute loss of monolayer coverage, resistance, and metabolism, coupled with increased number of apoptotic cells. Conversely, the other three ONCs tested displayed little loss of monolayer integrity; however, they exhibited differential coating-dependent increased apoptosis and up to 40-45% initial reduction in cell metabolism. Moreover, incinerated byproducts of ONCs exhibited significant loss of monolayer coverage and integrity, increased necrosis, with little evidence of monolayer re-establishment. These findings indicate that characteristics of organic coating type largely determine the mechanism of cytotoxicity and the ability of the monolayer to recover. Use of high content screening coupled with traditional in vitro assays proves to serve as a rapid pulmonary toxicity assessment tool to help define prevention by targeted physicochemical material properties design strategies.
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Affiliation(s)
- Todd A Stueckle
- Health Effects Laboratory Division , National Institute for Occupational Safety and Health , Morgantown , West Virginia 26505 , United States
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18
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Smith P, Jeffers LA, Koval M. Effects of different routes of endotoxin injury on barrier function in alcoholic lung syndrome. Alcohol 2019; 80:81-89. [PMID: 31278041 DOI: 10.1016/j.alcohol.2018.08.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 08/14/2018] [Accepted: 08/15/2018] [Indexed: 12/14/2022]
Abstract
In the lung, chronic alcohol consumption is a risk factor for acute respiratory distress syndrome (ARDS), a disorder that can be fatal due to airspace flooding. The severity of pulmonary edema is controlled by multiple barriers, and in particular the alveolar epithelial barrier and pulmonary microvasculature. However, to date, the effects of chronic alcohol ingestion on both of these barriers in the lung has not been directly and simultaneously measured. In addition the effects of alcohol on systemic, indirect lung injury versus direct injury have not been compared. In this study, we used tissue morphometry and Evans Blue permeability assays to assess the effects of alcohol and endotoxemia injury on pulmonary barrier function comparing intraperitoneal (IP) administration of lipopolysaccharide (LPS) to intratracheal (IT) administration. Consistent with previous reports, we found that in alcohol-fed mice, the alveolar barrier was impaired, allowing Evans Blue to permeate into the airspaces. Moreover, IT administered LPS caused a significant breach of both the alveolar epithelial and vascular barriers in alcohol-fed mice, whereas the endothelial barrier was less affected in response to IP administered LPS. The alveolar barrier of control mice remained intact for both IP and IT administered LPS. However, both injuries caused significant interstitial edema, independently of whether the mice were fed alcohol or not. These data suggest that in order to properly target pulmonary edema due to alcoholic lung syndrome, both the alveolar and endothelial barriers need to be considered as well as the nature of the "second hit" that initiates ARDS.
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19
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Kim N, Han DH, Suh MW, Lee JH, Oh SH, Park MK. Effect of lipopolysaccharide on diesel exhaust particle-induced junctional dysfunction in primary human nasal epithelial cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 248:736-742. [PMID: 30849591 DOI: 10.1016/j.envpol.2019.02.082] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/11/2019] [Accepted: 02/23/2019] [Indexed: 06/09/2023]
Abstract
OBJECTIVES Tight junctions (TJs) in the epithelium play a critical role in the formation of a paracellular epithelial barrier against the extracellular environment. Diesel exhaust particles (DEPs) disrupt the epithelial barrier. The aim of this study was to investigate how DEPs disrupt the epithelial barrier and whether Toll-like receptor 4 (TLR4) is involved in DEP-induced epithelial barrier dysfunction in primary human nasal epithelial (PHNE) cells. METHODS PHNE cells were cultured at an air-liquid interface (ALI) to create a fully differentiated in vivo-like model of the epithelium and then exposed to DEPs (particulate matter <4 μm) or lipopolysaccharide (LPS) alone (mono-exposure) and DEPs plus LPS (co-exposure) at the apical side of the PHNE. TJ formation and integrity were monitored by measuring transepithelial electric resistance (TEER) and fluorescently labeled dextran permeability. The expression of TJ proteins was assessed by confocal microscopy and a biochemical assay. RESULTS PHNE cell viability was reduced in a time- and dose-dependent manner following DEP exposure. TEER was significantly decreased at ALI day 20 but not at day 12 following DEP exposure. The dextran permeability of the PHNE was significantly increased at both ALI day 12 and day 20 following DEP exposure. The increased dextran permeability recovered to that of the control following co-exposure to DEPs plus LPS. In the presence of DEPs, the membrane expression of myosin light chain kinase (MLCK) was dramatically increased, and the expression of occludin, ZO1, claudin-1, and E-cadherin was significantly decreased. Co-exposure to DEPs plus LPS significantly reduced membrane MLCK, claudin-1, and E-cadherin but increased occludin and ZO1 expression at ALI day 12. CONCLUSION The activation of TLR4 by LPS inhibits MLCK trafficking to the plasma membrane, and this increased during DEP exposure, resulting in increased occludin expression at the plasma membrane that partially recovered TJ barrier dysfunction following DEP exposure.
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Affiliation(s)
- Nahyun Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Doo Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Myung-Whan Suh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea; Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Republic of Korea
| | - Jun Ho Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea; Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Republic of Korea
| | - Seung-Ha Oh
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea; Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Republic of Korea
| | - Moo Kyun Park
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea; Sensory Organ Research Institute, Seoul National University Medical Research Center, Seoul, Republic of Korea.
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20
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The Basic Science and Molecular Mechanisms of Lung Injury and Acute Respiratory Distress Syndrome. Int Anesthesiol Clin 2019; 56:1-25. [PMID: 29227309 DOI: 10.1097/aia.0000000000000177] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Burgess JK, Heijink IH. The Safety and Efficiency of Addressing ARDS Using Stem Cell Therapies in Clinical Trials. STEM CELL-BASED THERAPY FOR LUNG DISEASE 2019. [PMCID: PMC7121814 DOI: 10.1007/978-3-030-29403-8_12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Janette K. Burgess
- The University of Groningen, University Medical Center Groningen, Department of Pathology and Medical Biology, Groningen, The Netherlands
| | - Irene H. Heijink
- The University of Groningen, University Medical Center Groningen, Department of Pathology and Medical Biology, Groningen, The Netherlands
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22
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Sturrock A, Woller D, Freeman A, Sanders K, Paine R. Consequences of Hypoxia for the Pulmonary Alveolar Epithelial Cell Innate Immune Response. THE JOURNAL OF IMMUNOLOGY 2018; 201:3411-3420. [PMID: 30381478 DOI: 10.4049/jimmunol.1701387] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 10/02/2018] [Indexed: 11/19/2022]
Abstract
Pulmonary innate immune responses involve a highly regulated multicellular network to defend the enormous surface area of the lung. Disruption of these responses renders the host susceptible to pneumonia. Alveolar epithelial cells (AEC) are a critical source of innate immune molecules such as GM-CSF, which determine the functional maturation of alveolar macrophages. In many pulmonary diseases, heterogeneous ventilation leads to regional hypoxia in the lung. The effect of hypoxia on AEC innate immune function is unknown. We now report that exposure of primary murine AEC to hypoxia (1% oxygen) for 24 h results in significant suppression of key innate immune molecules, including GM-CSF, CCL2, and IL-6. This exposure did not cause toxicity but did induce stabilization of hypoxia-inducible factor 1α protein (HIF-1α) and shift to glycolytic metabolism. Focusing on GM-CSF, we found that hypoxia greatly decreased the rate of GM-CSF transcription. Hypoxia both decreased NF-κB signaling in AEC and induced chromosomal changes, resulting in decreased accessibility in the GM-CSF proximal promoter of target sequences for NF-κB binding. In mice exposed to hypoxia in vivo (12% oxygen for 2 d), lung GM-CSF protein expression was reduced. In vivo phagocytosis of fluorescent beads by alveolar macrophages was also suppressed, but this effect was reversed by treatment with GM-CSF. These studies suggest that in critically ill patients, local hypoxia may contribute to the susceptibility of poorly ventilated lung units to infection through complementary effects on several pathways, reducing AEC expression of GM-CSF and other key innate immune molecules.
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Affiliation(s)
- Anne Sturrock
- Department of Veterans Affairs Medicine Center, Salt Lake City, UT 84148; and.,Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132
| | - Diana Woller
- Department of Veterans Affairs Medicine Center, Salt Lake City, UT 84148; and.,Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132
| | - Andrew Freeman
- Department of Veterans Affairs Medicine Center, Salt Lake City, UT 84148; and.,Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132
| | - Karl Sanders
- Department of Veterans Affairs Medicine Center, Salt Lake City, UT 84148; and.,Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132
| | - Robert Paine
- Department of Veterans Affairs Medicine Center, Salt Lake City, UT 84148; and .,Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132
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23
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Sim TY, Harith HH, Tham CL, Md Hashim NF, Shaari K, Sulaiman MR, Israf DA. The Protective Effects of a Synthetic Geranyl Acetophenone in a Cellular Model of TNF-α-Induced Pulmonary Epithelial Barrier Dysfunction. Molecules 2018; 23:molecules23061355. [PMID: 29874809 PMCID: PMC6100020 DOI: 10.3390/molecules23061355] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 05/19/2018] [Accepted: 05/25/2018] [Indexed: 01/19/2023] Open
Abstract
Alveolar epithelial barrier dysfunction contributes to lung edema and can lead to acute lung injury (ALI). The features include increased epithelial permeability, upregulation of inflammatory mediators and downregulation of junctional complex molecules; these changes are often induced by inflammation. tHGA is an acetophenone analogue with therapeutic potential in asthma. Its therapeutic potential in ALI is presently unknown. Herein, the effects of tHGA on epithelial barrier dysfunction were determined in TNF-α-induced human alveolar epithelial cells. The anti-inflammatory properties of tHGA were assessed by monocyte adhesion assay and analysis of MCP-1 and ICAM-1 expression. The epithelial barrier function was assessed by paracellular permeability and transepithelial electrical resistance (TEER) assays, and analysis of junctional complex molecules expression. To elucidate the mechanism of action, the effects of tHGA on the NF-κB and MAPK pathways were determined. Gene and protein expression were analyzed by RT-PCR and Western blotting or ELISA, respectively. tHGA suppressed leukocyte adhesion to TNF-α-induced epithelium and reduced MCP-1 and ICAM-1 gene expression and secretion. tHGA also increased TEER readings, reduced epithelial permeability and enhanced expression of junctional complex molecules (zona occludens-1, occludin and E-cadherin) in TNF-α-induced cells. Correspondingly, the NF-κB, ERK and p38 MAPK pathways were also inhibited by tHGA. These findings suggest that tHGA is able to preserve alveolar epithelial barrier function in response to acute inflammation, via its anti-inflammatory activity and stabilization of epithelial barrier integrity, mediated by NF-κB, ERK and p38 MAPK signaling.
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Affiliation(s)
- Tee Yee Sim
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Hanis Hazeera Harith
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Chau Ling Tham
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Nur Fariesha Md Hashim
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Khozirah Shaari
- Natural Products Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Mohd Roslan Sulaiman
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Daud Ahmad Israf
- Department of Biomedical Science, Faculty of Medicine & Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
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24
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Lewis JB, Bodine JS, Gassman JR, Muñoz SA, Milner DC, Dunaway TM, Egbert KM, Monson TD, Broberg DS, Arroyo JA, Reynolds PR. Transgenic up-regulation of Claudin-6 decreases fine diesel particulate matter (DPM)-induced pulmonary inflammation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:18179-18188. [PMID: 29696536 DOI: 10.1007/s11356-018-1985-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 04/09/2018] [Indexed: 06/08/2023]
Abstract
Claudin-6 (Cldn6) is a tetraspanin transmembrane protein that contributes to tight junctional complexes and has been implicated in the maintenance of lung epithelial barriers. In the present study, we tested the hypothesis that genetic up-regulation of Cldn-6 influences inflammation in mice exposed to short-term environmental diesel particulate matter (DPM). Mice were subjected to ten exposures of nebulized DPM (PM2.5) over a period of 20 days via a nose-only inhalation system (Scireq, Montreal, Canada). Using real-time RT-PCR, we discovered that the Cldn6 gene was up-regulated in control mice exposed to DPM and in lung-specific transgenic mice that up-regulate Cldn-6 (Cldn-6 TG). Interestingly, DPM did not further enhance Cldn-6 expression in Cldn-6 TG mice. DPM caused increased cell diapedesis into bronchoalveolar lavage fluid (BALF) from control mice; however, Cldn-6 TG mice had less total cells and PMNs in BALF following DPM exposure. Because Cldn-6 TG mice had diminished cell diapedesis, other inflammatory intermediates were screened to characterize the impact of increased Cldn-6 on inflammatory signaling. Cytokines that mediate inflammatory responses including TNF-α and IL-1β were differentially regulated in Cldn6 TG mice and controls following DPM exposure. These results demonstrate that epithelial barriers organized by Cldn-6 mediate, at least in part, diesel-induced inflammation. Further work may show that Cldn-6 is a key target in understanding pulmonary epithelial gateways exacerbated by environmental pollution.
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Affiliation(s)
- Joshua B Lewis
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Jared S Bodine
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Jason R Gassman
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Samuel Arce Muñoz
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Dallin C Milner
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Todd M Dunaway
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Kaleb M Egbert
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Troy D Monson
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Dallin S Broberg
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Juan A Arroyo
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
| | - Paul R Reynolds
- Lung and Placenta Research Laboratory, Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA.
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25
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Aasen T, Johnstone S, Vidal-Brime L, Lynn KS, Koval M. Connexins: Synthesis, Post-Translational Modifications, and Trafficking in Health and Disease. Int J Mol Sci 2018; 19:ijms19051296. [PMID: 29701678 PMCID: PMC5983588 DOI: 10.3390/ijms19051296] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/20/2018] [Accepted: 04/21/2018] [Indexed: 02/06/2023] Open
Abstract
Connexins are tetraspan transmembrane proteins that form gap junctions and facilitate direct intercellular communication, a critical feature for the development, function, and homeostasis of tissues and organs. In addition, a growing number of gap junction-independent functions are being ascribed to these proteins. The connexin gene family is under extensive regulation at the transcriptional and post-transcriptional level, and undergoes numerous modifications at the protein level, including phosphorylation, which ultimately affects their trafficking, stability, and function. Here, we summarize these key regulatory events, with emphasis on how these affect connexin multifunctionality in health and disease.
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Affiliation(s)
- Trond Aasen
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
| | - Scott Johnstone
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, P.O. Box 801394, Charlottesville, VI 22908, USA.
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TT, UK.
| | - Laia Vidal-Brime
- Translational Molecular Pathology, Vall d'Hebron Institute of Research (VHIR), Autonomous University of Barcelona, CIBERONC, 08035 Barcelona, Spain.
| | - K Sabrina Lynn
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA.
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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26
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Pan Y, Liu Y, Wang L, Xue F, Hu Y, Hu R, Xu C. MKP-1 attenuates LPS-induced blood-testis barrier dysfunction and inflammatory response through p38 and IκBα pathways. Oncotarget 2018; 7:84907-84923. [PMID: 27783995 PMCID: PMC5356708 DOI: 10.18632/oncotarget.12823] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 10/04/2016] [Indexed: 01/14/2023] Open
Abstract
Sertoli cells create a local tolerogenic microenvironment to maintain testicular immune privilege especially through the formation of a blood-testis barrier (BTB). However, the molecular mechanisms underlying the immune modulation function and BTB dynamics of Sertoli cells remained elusive. MAP phosphatase (MKP)-1 acts as a crucial negative regulator of the inflammatory response. Nevertheless, the role of MKP-1 in regulating Sertoli cells has not been elucidated. In this study, we have for the first time uncovered distinct cellular localization of MKP-1 in the cells at different stages of mouse testis, and the level of MKP-1 expression was significantly up-regulated by LPS-induced acute testis inflammation. In addition, MKP-1 staining was strongly detected in nuclei and peri-nuclear regions of cytoplasm in the Sertoli cells, and it was presented at Sertoli cell tight junctions (TJs) at stages VII-VIII after LPS treatment. Moreover, we demonstrated that MKP-1 was capable of attenuating LPS-induced decrease of occludin by interaction with p38 MAP kinase and IκBα molecules. Taken together, our data highlight that MKP-1 was an important endogenous suppressor of innate immune responses involved in the regulation of BTB barrier dynamic. This study thus might offer novel targets for treating inflammatory diseases in the testis.
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Affiliation(s)
- Yiqing Pan
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China
| | - Yue Liu
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China
| | - Li Wang
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China
| | - Feng Xue
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China.,Laboratory of Dermatology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yanqin Hu
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China
| | - Ran Hu
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Chen Xu
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Shanghai Key Laboratory of Reproductive Medicine, Shanghai 200025, China
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27
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Wittekindt OH. Tight junctions in pulmonary epithelia during lung inflammation. Pflugers Arch 2016; 469:135-147. [PMID: 27921210 PMCID: PMC5203840 DOI: 10.1007/s00424-016-1917-3] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 11/23/2016] [Accepted: 11/27/2016] [Indexed: 12/31/2022]
Abstract
Inflammatory lung diseases like asthma bronchiale, chronic obstructive pulmonary disease and allergic airway inflammation are widespread public diseases that constitute an enormous burden to the health systems. Mainly classified as inflammatory diseases, the treatment focuses on strategies interfering with local inflammatory responses by the immune system. Inflammatory lung diseases predispose patients to severe lung failures like alveolar oedema, respiratory distress syndrome and acute lung injury. These life-threatening syndromes are caused by increased permeability of the alveolar and airway epithelium and exudate formation. However, the mechanism underlying epithelium barrier breakdown in the lung during inflammation is elusive. This review emphasises the role of the tight junction of the airway epithelium as the predominating structure conferring epithelial tightness and preventing exudate formation and the impact of inflammatory perturbations on their function.
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Affiliation(s)
- Oliver H Wittekindt
- Institute of General Physiology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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28
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Lewis JB, Milner DC, Lewis AL, Dunaway TM, Egbert KM, Albright SC, Merrell BJ, Monson TD, Broberg DS, Gassman JR, Thomas DB, Arroyo JA, Reynolds PR. Up-Regulation of Claudin-6 in the Distal Lung Impacts Secondhand Smoke-Induced Inflammation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:E1018. [PMID: 27763528 PMCID: PMC5086757 DOI: 10.3390/ijerph13101018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 09/30/2016] [Accepted: 10/13/2016] [Indexed: 01/06/2023]
Abstract
It has long been understood that increased epithelial permeability contributes to inflammation observed in many respiratory diseases. Recently, evidence has revealed that environmental exposure to noxious material such as cigarette smoke reduces tight junction barrier integrity, thus enhancing inflammatory conditions. Claudin-6 (Cldn6) is a tetraspanin transmembrane protein found within the tight junctional complex and is implicated in maintaining lung epithelial barriers. To test the hypothesis that increased Cldn6 ameliorates inflammation at the respiratory barrier, we utilized the Tet-On inducible transgenic system to conditionally over-express Clnd6 in the distal lung. Cldn6 transgenic (TG) and control mice were continuously provided doxycycline from postnatal day (PN) 30 until euthanasia date at PN90. A subset of Cldn6 TG and control mice were also subjected to daily secondhand tobacco smoke (SHS) via a nose only inhalation system from PN30-90 and compared to room air (RA) controls. Animals were euthanized on PN90 and lungs were harvested for histological and molecular characterization. Bronchoalveolar lavage fluid (BALF) was procured for the assessment of inflammatory cells and molecules. Quantitative RT-PCR and immunoblotting revealed increased Cldn6 expression in TG vs. control animals and SHS decreased Cldn6 expression regardless of genetic up-regulation. Histological evaluations revealed no adverse pulmonary remodeling via Hematoxylin and Eosin (H&E) staining or any qualitative alterations in the abundance of type II pneumocytes or proximal non-ciliated epithelial cells via staining for cell specific propeptide of Surfactant Protein-C (proSP-C) or Club Cell Secretory Protein (CCSP), respectively. Immunoblotting and qRT-PCR confirmed the differential expression of Cldn6 and the pro-inflammatory cytokines TNF-α and IL-1β. As a general theme, inflammation induced by SHS exposure was influenced by the availability of Cldn6. These data reveal captivating information suggesting a role for Cldn6 in lungs exposed to tobacco smoke. Further research is critically necessary in order to fully explain roles for tight junctional components such as Cldn6 and other related molecules in lungs coping with exposure.
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Affiliation(s)
- Joshua B Lewis
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Dallin C Milner
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Adam L Lewis
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Todd M Dunaway
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Kaleb M Egbert
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Scott C Albright
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Brigham J Merrell
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Troy D Monson
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Dallin S Broberg
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Jason R Gassman
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Daniel B Thomas
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Juan A Arroyo
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
| | - Paul R Reynolds
- Lung and Placenta Research Laboratory, Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA.
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29
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Schlingmann B, Overgaard CE, Molina SA, Lynn KS, Mitchell LA, Dorsainvil White S, Mattheyses AL, Guidot DM, Capaldo CT, Koval M. Regulation of claudin/zonula occludens-1 complexes by hetero-claudin interactions. Nat Commun 2016; 7:12276. [PMID: 27452368 PMCID: PMC4962485 DOI: 10.1038/ncomms12276] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 06/15/2016] [Indexed: 01/06/2023] Open
Abstract
Claudins are tetraspan transmembrane tight-junction proteins that regulate epithelial barriers. In the distal airspaces of the lung, alveolar epithelial tight junctions are crucial to regulate airspace fluid. Chronic alcohol abuse weakens alveolar tight junctions, priming the lung for acute respiratory distress syndrome, a frequently lethal condition caused by airspace flooding. Here we demonstrate that in response to alcohol, increased claudin-5 paradoxically accompanies an increase in paracellular leak and rearrangement of alveolar tight junctions. Claudin-5 is necessary and sufficient to diminish alveolar epithelial barrier function by impairing the ability of claudin-18 to interact with a scaffold protein, zonula occludens 1 (ZO-1), demonstrating that one claudin affects the ability of another claudin to interact with the tight-junction scaffold. Critically, a claudin-5 peptide mimetic reverses the deleterious effects of alcohol on alveolar barrier function. Thus, claudin controlled claudin-scaffold protein interactions are a novel target to regulate tight-junction permeability.
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Affiliation(s)
- Barbara Schlingmann
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Christian E Overgaard
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Samuel A Molina
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - K Sabrina Lynn
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Leslie A Mitchell
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA
| | - StevenClaude Dorsainvil White
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Alexa L Mattheyses
- Department of Cell Biology, Emory University, Atlanta, Georgia 30322, USA
| | - David M Guidot
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA.,Atlanta Veterans Affairs Medical Center, Decatur, Georgia 30033, USA
| | - Christopher T Capaldo
- Department of Pathology; Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA.,Department of Cell Biology, Emory University, Atlanta, Georgia 30322, USA
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30
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Schlingmann B, Molina SA, Koval M. Claudins: Gatekeepers of lung epithelial function. Semin Cell Dev Biol 2015; 42:47-57. [PMID: 25951797 DOI: 10.1016/j.semcdb.2015.04.009] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 04/24/2015] [Indexed: 12/25/2022]
Abstract
The lung must maintain a proper barrier between airspaces and fluid filled tissues in order to maintain lung fluid balance. Central to maintaining lung fluid balance are epithelial cells which create a barrier to water and solutes. The barrier function of these cells is mainly provided by tight junction proteins known as claudins. Epithelial barrier function varies depending on the different needs within the segments of the respiratory tree. In the lower airways, fluid is required to maintain mucociliary clearance, whereas in the terminal alveolar airspaces a thin layer of surfactant enriched fluid lowers surface tension to prevent airspace collapse and is critical for gas exchange. As the epithelial cells within the segments of the respiratory tree differ, the composition of claudins found in these epithelial cells is also different. Among these differences is claudin-18 which is uniquely expressed by the alveolar epithelial cells. Other claudins, notably claudin-4 and claudin-7, are more ubiquitously expressed throughout the respiratory epithelium. Claudin-5 is expressed by both pulmonary epithelial and endothelial cells. Based on in vitro and in vivo model systems and histologic analysis of lungs from human patients, roles for specific claudins in maintaining barrier function and protecting the lung from the effects of acute injury and disease are being identified. One surprising finding is that claudin-18 and claudin-4 control lung cell phenotype and inflammation beyond simply maintaining a selective paracellular permeability barrier. This suggests claudins have more nuanced roles for the control of airway and alveolar physiology in the healthy and diseased lung.
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Affiliation(s)
- Barbara Schlingmann
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Samuel A Molina
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Michael Koval
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States.
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31
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Overgaard CE, Schlingmann B, Dorsainvil White S, Ward C, Fan X, Swarnakar S, Brown LAS, Guidot DM, Koval M. The relative balance of GM-CSF and TGF-β1 regulates lung epithelial barrier function. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1212-23. [PMID: 25888574 DOI: 10.1152/ajplung.00042.2014] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/09/2015] [Indexed: 11/22/2022] Open
Abstract
Lung barrier dysfunction is a cardinal feature of the acute respiratory distress syndrome (ARDS). Alcohol abuse, which increases the risk of ARDS two- to fourfold, induces transforming growth factor (TGF)-β1, which increases epithelial permeability and impairs granulocyte/macrophage colony-stimulating factor (GM-CSF)-dependent barrier integrity in experimental models. We hypothesized that the relative balance of GM-CSF and TGF-β1 signaling regulates lung epithelial barrier function. GM-CSF and TGF-β1 were tested separately and simultaneously for their effects on lung epithelial cell barrier function in vitro. TGF-β1 alone caused an ∼ 25% decrease in transepithelial resistance (TER), increased paracellular flux, and was associated with projections perpendicular to tight junctions ("spikes") containing claudin-18 that colocalized with F-actin. In contrast, GM-CSF treatment induced an ∼ 20% increase in TER, decreased paracellular flux, and showed decreased colocalization of spike-associated claudin-18 with F-actin. When simultaneously administered to lung epithelial cells, GM-CSF antagonized the effects of TGF-β1 on epithelial barrier function in cultured cells. Given this, GM-CSF and TGF-β1 levels were measured in bronchoalveolar lavage (BAL) fluid from patients with ventilator-associated pneumonia and correlated with markers for pulmonary edema and patient outcome. In patient BAL fluid, protein markers of lung barrier dysfunction, serum α2-macroglobulin, and IgM levels were increased at lower ratios of GM-CSF/TGF-β1. Critically, patients who survived had significantly higher GM-CSF/TGF-β1 ratios than nonsurviving patients. This study provides experimental and clinical evidence that the relative balance between GM-CSF and TGF-β1 signaling is a key regulator of lung epithelial barrier function. The GM-CSF/TGF-β1 ratio in BAL fluid may provide a concentration-independent biomarker that can predict patient outcomes in ARDS.
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Affiliation(s)
- Christian E Overgaard
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia
| | - Barbara Schlingmann
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia
| | - StevenClaude Dorsainvil White
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia
| | - Christina Ward
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia
| | - Xian Fan
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Snehasikta Swarnakar
- Drug Development Diagnostics and Biotechnology, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Lou Ann S Brown
- Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Division of Neonatology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - David M Guidot
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Department of Cell Biology, Emory University, Atlanta, Georgia;
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32
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Luscinskas FW, Leick M, Newton G, Nusrat A. Introduction for the special issue on "Tissue Barriers in Inflammation". Tissue Barriers 2015; 3:e1015825. [PMID: 25927017 PMCID: PMC4389789 DOI: 10.1080/21688370.2015.1015825] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This issue of Tissue Barriers contains the inaugural special issue devoted to recent advances in barrier function of endothelial and epithelial cells. We used this opportunity to invite experts in vascular endothelial cell biology and epithelial cell biology to comment on critical questions and problems in permeability of organ and tissue barriers, and to provide insight into common areas in these fields, namely how these cells maintain homeostasis and response to injury and infection. To complement these reviews, this issue also contains four research articles that explore specific questions related respiratory and intestinal epithelial cell function.
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Affiliation(s)
- Francis W Luscinskas
- Center for Excellence in Vascular Biology; Department
of Pathology; Brigham and Women's Hospital; Harvard Medical
School; Boston, MA USA
| | - Marion Leick
- Center for Excellence in Vascular Biology; Department
of Pathology; Brigham and Women's Hospital; Harvard Medical
School; Boston, MA USA
| | - Gail Newton
- Center for Excellence in Vascular Biology; Department
of Pathology; Brigham and Women's Hospital; Harvard Medical
School; Boston, MA USA
| | - Asma Nusrat
- Center for Excellence in Vascular Biology; Department
of Pathology; Brigham and Women's Hospital; Harvard Medical
School; Boston, MA USA
- Present affiliation: Pathology and Laboratory
Medicine; Emory University School of Medicine; Atlanta, GA
USA
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